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Tiny particles embedded in ancient Canadian rocks have provided new clues about what might have triggered Earth’s deadliest mass extinction. The ultimate cause, researchers say, might be globe-smothering clouds of toxic ash similar to that spewed by modern-day coal-fired power plants.
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| The die-off, which occurred worldwide about 250 million years ago at the end of the Permian period, was even more extensive than the one that wiped out the dinosaurs |
| Geochemist Stephen Grasby |
| analyzed rocks from just before the Permian mass extinction, they noticed |
| tiny bubble-filled particles called cenospheres |
| These frothy little blobs form only when molten coal spews into the atmosphere |
| they must have been created when massive amounts of molten rock—more than 1 trillion metric tons—erupted through overlying coal deposits in Siberia |
| loaded with toxic metals such as chromium and arsenic |
| they would have converted surface waters into a toxic soup |
| “The evidence is pretty compelling |
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